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May 30, 2008 (Indianapolis) -- If you have high blood pressure or are extremely overweight, walking may hold the key to improved heart health.
That's the message from researchers who spoke here this week at the annual meeting of the American College of Sports Medicine (ACSM).
A Korean study shows that walking just 40 minutes a day lowered blood pressure in people with hypertension. A U.S. study suggested that taking a stroll offers cardiovascular benefits for people who are morbidly obese.
The Korean researchers studied 23 men with prehypertension or hypertension. "Normal" blood pressure is a measurement of less than 120/80. Hypertension is defined as a reading of 140 over 90 or greater. Those with blood pressure readings between normal blood pressure and high blood pressure are considered to have prehypertension.
The researchers measured the men's blood pressure following a 40-minute brisk walking session and four, 10-minute brisk walking bouts. What's brisk? About 3 to 4 miles per hour, says Saejong Park, PhD, of the Korea Institute of Sport Science in Seoul.
Blood pressure dropped by similar amounts after each type of exercise session. The top number in the blood pressure reading dropped about 5 points after the 40-minute walk and 3 points after the four 10-minute walks, Park tells WebMD. The bottom number of the blood pressure reading dropped about 2 points for both walking sessions.
While longer studies are needed, "we think the benefits will be sustained over time if the men keep exercising," Park says.
The bottom line, she tells WebMD, is that you have a choice when it comes to exercise. "Some people like to work out all at once, but others say they can't comply with an exercise program because they have no time. These findings suggest people with time crunches and busy schedules can fit bits of exercise in throughout the day and reap the same health benefits."
The findings are in line with ACSM recommendations, which call for healthy adults to engage in at least 30 minutes of moderate physical activity five days a week. The guidelines state that three 10-minute sessions are as effective as one longer session.
Jeffrey A. Ross, DPM, a clinical professor of medicine at Baylor College of Medicine in Houston, recommends alternating walking with other activities.
"Instead of walking seven days a week, take a day off and go swimming or biking. That way you'll work out different muscles and reduce your chance of overuse injuries," Ross says.
The U.S. study involved 14 morbidly obese patients who were scheduled to undergo weight loss surgery. Their average body mass index (BMI) was 46; a person with a BMI of 40 or over is considered to be morbidly obese.
Patients were asked to walk 1 mile at as brisk a pace as possible. They were able to stop and take breaks, but most walked the mile in under 30 minutes, says Thomas Spring, MS, a senior exercise physiologist at William Beaumont Hospital in Royal Oak, Mich.
Results showed that all 14 "got their heart rate up to an adequate level to have benefits in term of cardiovascular health," Spring tells WebMD. "Walking is a great way for the overweight and obese to begin an exercise program, but always check with your doctor before starting any exercise program."